class_docstr: Represents custom prediction model implementation. This model does not require to be fitted as the model has to be fully defined.
code: def clone(self):
      return CustomEquationModel(self.custom_func, self.parent_nodes)
  
imports: import ast
  import logging
  import re
  from typing import Tuple
  import networkx
  import numpy
  import scipy.stats
  from dowhy.gcm import AdditiveNoiseModel, EmpiricalDistribution, ScipyDistribution, StructuralCausalModel
  from dowhy.gcm.causal_mechanisms import StochasticModel
  from dowhy.gcm.causal_models import PARENTS_DURING_FIT
  from dowhy.gcm.ml.prediction_model import PredictionModel
  from dowhy.gcm.util.general import shape_into_2d
  from dowhy.graph import get_ordered_predecessors
label_desc: Use image node_id 4 for calling the CustomEquationModel obj's underlying member method code with example usage: obj.clone() and returns: CustomEquationModel